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1640s, from French décapitation, from Medieval Latin decapitationem (nominative decapitatio), noun of action from past participle stem of Late Latin decapitare (see decapitate).
decapitation de·cap·i·ta·tion (dĭ-kāp'ĭ-tā'shən)
The removal of a head, as of an animal, a fetus, or a bone.
a mode of executing capital punishment by which the head is severed from the body. The ancient Greeks and Romans regarded it as a most honourable form of death. Before execution the criminal was tied to a stake and whipped with rods. In early times an ax was used, but later a sword, which was considered a more honourable instrument of death, was used for Roman citizens. Ritual decapitation known as seppuku was practiced in Japan from the 15th through the 19th century. One symbolic consequence of the French Revolution was the extension of the privilege of beheading to criminals of ordinary birth, by means of the guillotine.